This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:
apport-collect 1752165 and then change the status of the bug to 'Confirmed'. If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'. This change has been made by an automated script, maintained by the Ubuntu Kernel Team. ** Changed in: linux (Ubuntu) Status: New => Incomplete ** Tags added: artful -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1752165 Title: TB16 dock freezes X on hotplug when used with external displays Status in Dell Sputnik: New Status in linux package in Ubuntu: Incomplete Bug description: Precision 5520 with Quadro GPU. Latest Ubuntu 16.04, kernel Linux REDACTED 4.13.0-36-generic #40~16.04.1-Ubuntu SMP Fri Feb 16 23:25:58 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux, latest BIOS 1.7.0 released 12/15/2017. If it can be of any help, I can get this tested on an XPS 9560 (GTX 1050) too. Steps to reproduce: 1. Plug in monitors into DP and miniDP on the dock. In my case, DP-to-DVI cables are used, but I doubt that it matters. 2. Ubuntu 16.04 GNOME + nVidia drivers with PRIME. 3. Select nVidia GPU in PRIME settings, reboot if needed. 4. Either boot with the dock connected or connect it after booting into user session. 5. Set up monitors if necessary. At this point everything should be working fine. 6. Disconnect the dock, give it a moment to adjust to the new window layout etc. 7. Re-connect the dock. Within a few seconds laptop screen should freeze and external monitors should remain blank, as if not connected. 8. Disconnect the dock. Within a few seconds laptop screen should unfreeze. There is a small chance that it won't if you repeat this procedure multiple times. Errors in dmesg indicate that i915 driver is somehow involved: [ 328.966128] [drm:intel_dp_set_idle_link_train [i915]] *ERROR* Timed out waiting for DP idle patterns [ 328.967848] [drm:intel_wait_ddi_buf_idle [i915]] *ERROR* Timeout waiting for DDI BUF B idle bit [ 329.048839] [drm:intel_dp_set_idle_link_train [i915]] *ERROR* Timed out waiting for DP idle patterns [ 329.050547] [drm:intel_wait_ddi_buf_idle [i915]] *ERROR* Timeout waiting for DDI BUF C idle bit The kernel logs are flooded with these between steps 7 and 8 above. This behaviour does not occur when Intel GPU is selected in PRIME settings or when nouveau is used. However, nouveau performance leaves a lot to be desired, particularly with 3D acceleration in Windows 10 VMs. I have tried nvidia_drm.modeset=1 in boot options, but it doesn't make any difference. Other reports that may be related: https://devtalk.nvidia.com/default/topic/989704/linux/plugging-a -docking-station-w-two-monitors-into-a-quadro-m1000m-laptop-crashes- hangs-the-whole-machine/ - same error messages https://www.reddit.com/r/Dell/comments/5nas3t/tb16_dock_with_5510_ubuntulinux/ddzjlu8/?st=je63h7lw&sh=40bf8189 - "Connecting and disconnecting the TB16 sometimes freeze the laptop." https://www.dell.com/community/Sputnik/TB16-Dock-Linux- Support/m-p/5109128/highlight/true#M7466 - "Hot-plugging the screen does not work." To manage notifications about this bug go to: https://bugs.launchpad.net/dell-sputnik/+bug/1752165/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp